Immunoregulatory actions of polysaccharides from Chinese herbal medicine.

IMPORTANCE OF THE FIELD: Polysaccharides, one of main classes of bioactive substances from Chinese herbal medicine (CHM), have been indicated to have wide pharmacological activities, especially broad immunomodulatory and antitumour effects. However, their immunoregulatory mechanisms are still not fully understood yet. AREAS COVERED IN THIS REVIEW: Polysaccharides from CHM (CHMPS) are reviewed with focus on their immunoregulatory function, describing their immunoregulatory actions on immune organs, immune cells and immune molecules, and discussing their effects on cell surface receptors and cell signaling pathways. WHAT THE READER WILL GAIN: A better understanding of the immunoregulatory effects of CHMPS and their structure-function relationship. TAKE HOME MESSAGE: CHMPS can active or regulate the immune system including innate and adaptive responses, and have profound effects on different diseases. Through examining the molecular mechanisms of the immunomodulating effects of CHMPS, it can be shown that CHMPS have the potential to be an adjuvant in cancer therapies.